(Continuedfrom page 803) I suspect that
those ants on stilts are trying to bluff their
opponents into perceiving them as bigger
than they are. After all, only a strong, ma
ture colony-one too powerful to challenge
further-would produce so many big ants.
Sometimes, if a colony recognizes that it
can overwhelm its considerably weaker op
ponents, its workers become slave raiders.
They invade their opponents' nest. They kill
the queen and carry off the nectar-filled
honeypots as booty. Most important, they
steal the dead queen's brood. When these
young ants emerge, they will be unwitting
slaves, foraging for the dominant colony and
helping rear the offspring of its queen. They
thus better ensure her genes' survival.
Slavery is an occasional tactic of the
honey ants. Some ants, however, live solely
on slave labor. Polyergus, the red Amazon
ant, for instance, has large, piercing mandi
bles designed for a life of fighting. These
mandibles are useless in doing other work
such as foraging, hunting, or brood tending.
The Amazons thus must depend on slaves
captured from related species for the day-to
day business of living.
As a boy I often observed the spectacle of a
red Amazon raid (pages 806-807). I would
spot a column two to four meters long and
densely packed with the Amazons. I would
watch them pour into a neighbor's colony,
readily disposing of any defenders.
Slave raiders do not kill needlessly. In
fact, some use a propaganda pheromone.
They release this chemical, which throws
the defenders into a confused, disoriented
frenzy, while they grab up the brood.
Once the stolen young hatch in the raid
ers' nest, they are imprinted with the slave
makers' odors. They accept their enslavers
as their sisters and service their adopted col
ony as their own.
ANTS ARE SOMETIMES exploited by
other insects. A number of solitary
species have learned how to trick
ants into providing them a living.
Beetles are the most accomplished of
these freeloaders. They have cracked the
ants' chemical codes and tactile signals.
Some, which I call the highwayman beetles,
can locate an ant trail by scent. They then
approach food-laden ants scurrying along
this trail and mimic the ant colony's food
exchange signals. The ant, sensing the
proper signal, feeds the beetle.
Other beetles have learned to emit the
ants' very own scents (facing page). They
and their larvae can thus live unmolested
right inside an ant colony. They also trick
their host ants into feeding them and nursing
their larvae. Moreover, the larvae of these
beetles feed on the ants' brood. That the ants
do not recognize these parasites as foreigners
illustrates how rigidly ant behavior is domi
nated by chemical and tactile signals. Ants
do what they are programmed to do.
Yet years of ant watching have demon
strated over and over that these creatures
are far from simple. In fact, they have much
to teach us. For here in the insect world we
can observe societies that in many respects
are at least as complicated as our own.
We see, furthermore, that in nature such
social systems have evolved repeatedly. The
ants seem to be saying that on this planet it is
an advantage to be social. They cooperate
with virtuosity. They do not kill each other
recklessly. They do not waste energy. In the
evolutionary battlefield, they are survivors.
Yes, we can learn a lot from the ants.
The beetles that came to dinner... and stayed
MIMIC WITHOUT EQUAL, a short
winged beetle (Lomechusa strumosa)
wins adoptioninto the family of this
Europeanant by secretingirresistible
scents into dense clusters of bristles on
its back. The beetle can live only in the
ant nest.A worker antfeeds an adult
FORMICASANGUINEA,ABOUT15 TIMES LIFE-SIZE
beetle, top, totally oblivious of the large
beetle larva, at center, consuming an
ant larva unhindered. Two other workers
tend ant larvae, lower. The beetles also
eat theirown larvae, preventing
overpopulationof their species and the
total eliminationof their hosts.
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